This application seeks continuation of funding for the Substance Use and HIV Prevention Research in Minority Communities program (SUHPR) at the University of California San Francisco (UCSF). This training program addresses the urgent need highlighted in NIDA PAR-13-084, the 2013 National AIDS Strategy, and the 2012 NIDA Research Report on Drug Abuse and HIV/AIDS to promote clinical prevention research and reduce health disparities in vulnerable communities where substance use is a crucial public health concern. SUHPR also aims to increase the number of scientists from diverse backgrounds who attain NIH funding by providing a research education curriculum, mentoring, and pilot study funding to early-career clinical scientists (visiting professors or VPs) to secure multiyear funding to conduct innovative health disparities research at the intersection of HIV and substance use risk. The aims of this five-year project are to: 1) increase the capacity of VPs to conduct multidisciplinary prevention research that elucidates the links between substance use and HIV risk in underserved communities; 2) provide funding to conduct pilot clinical research that will yield data for substance-use-related presentations at national conferences and provide preliminary data for grant proposals to NIDA; 3) provide education, mentoring, and technical assistance in the development and submission of research grants to NIDA that focus on substance use, HIV prevention, and improving HIV care outcomes; and 4) engage former VPs to help expand their innovative clinical research programs targeting the intersection of HIV and substance use, leverage their experience to benefit current and future VPs, and hone their skills as independent researchers. To address aims 1-3 the SUHPR program will implement a summer program for early-career clinical scientists who have not yet obtained R01-level funding. Each VP will visit CAPS for three summers and attend seminars on HIV and substance use research, methods, and grant writing. SUHPR also includes parallel networking activities, such as attending national conferences and open access publishing. The SUHPR is structured across three consecutive six-week summer sessions. In the first summer, mentors will assist each VP to plan a pilot study. In the second summer, each VP will analyze the pilot data and draft a multiyear grant proposal that is peer reviewed. During the third summer, the VPs will obtain extensive feedback on their grant proposals, revise them, and submit them for extramural review. During the academic years between summers mentors will communicate with VPs at least monthly, supplemented by webinars and the program's custom web site. To fortify this intensive research education experience, the program will implement aim 4 by providing peer review and consultations to help VPs remain in the research pipeline and extend their programs of substance use and HIV-prevention research. We will also leverage successful former VPs for peer review with current VPs. Collectively completing specific aims 1-4 will accelerate the development of HIV and substance use health disparities research programs with high public health impact.